Improvement in punching metallic tubes



UNITED STATES PATENT OFFICE.

BENJAMIN MAOKERLEY, AOF NEW PETERSBURG., OHIO.

IMPROVEMENT IN PUNCHING METALLIC TUBES.

Specification forming part of Letters Patent No. 20,165, dated May 4,1858.

an end view; Fig. 4, a section in the line a:

of Fig. l; and Fig. 5, a representation of a portion of the machinedetached.

Similar letters indicate corresponding parts in all the drawings.

The mandrel a, which supports the tube b during the punching operation,is secured to the left-hand end of the platform A by means of the box e,the cap c, and a pair of bolts, (or it may be secured by any othersuitable device,) While the opposite end of said mandrel rests looselyin the bearings p p', located at the opposite end of said platform. Thebearing p, which loosely embraces about threefourths of the periphery ofthe mandrel a, is iirmly secured between the cheeks B B, which rise fromthe right-hand end of the platform A. The block h, which is securelyconfined in its place between the cheeks B B', has a vertical grooveformed in its face for the reception of the stock CZ of the punch d',the said punch-stock being retained in its guiding-groove by means ofthe clamps 'it' or other suitable fastenings. A crank-shaft f works inapertures in the upper ends of the cheeks B B, or in journal-boxescombined with said cheeks. The stock of the punch d is combined with thecentral crank or an eccentric on the shaft f by Ineans of the hingedheadpiece g and the strap g, substantially as represented in thedrawings. A socket n is formed in the loose end of the mandrel a, andimmediat-ely beneath the punch d an aperture m is formed in theperiphery of the mandrel, which leads into the said socket n, andthrough which the clippings of the punch are discharged into saidsocket. Adetent of the shape particularly shown in Fig. 5 is secured bymeans of a fulcrum pin or screw to the right-hand side of the cheek B.The laterallyprojecting tooth at the inner end of the detent jcorresponds in size and shape with that of the punch d', and the saiddetent is placed in such a position relatively to that of the punch dthat after the punch has formed one aperture in the tube bthe properposition for the next succeeding aperture to be formed in said tube willbe indicated with the utmost precision, and the tube be held securelyduring the punching operation, by pressing the tooth of the detent jinto the aforesaid aperture and retaining it in that position until thebefore-mentioned succeeding aperture has been formed by the punch. Itwill therefore be perceived that when it is desired to form a doubleseries of spirally-located apertures in a cylinder, which shall bediametrically opposite each other, itis only necessary to properlylocate the commencing apertures of each series to have al1 thesucceeding apertures of the same occupy their appropriate relativepositions from end to end of the eylinder. A gouge-shaped wedge k, whoselength corresponds with that of the tube to be punched, is inserted intothe mouth of the tube and is pressed between the under side thereof andthe under side of the mandrel, for the purpose of keeping the upper sideof the mandrel firmly pressed against the upper side of the tub'e duringthe operation of punching apertures therein.

Having thus fully described my improved machine for formingcorresponding series of s pirall y-located apertures in cylindricaltubes, what I claim therein as my invention, and desire to secure byLetters Patent, is

l. The combination of the mandrel a, the punch CZ', and the detent j,substantial-ly in the manner and for the purpose herein set forth.

2. The use of the gouge-shaped wedge 7c, in combination with the mandrela and the punch d', substantially in the manner and for the purposeherein set forth.

The above specification of my improved machine for punchingspirally-located apertures in metallic tubes signed and witnessed this27 th day of February, 1858.

BENJAMIN MACKERLEY. Vitnesses:

HENRY HIATT, JAMES E. MAOKERLEY.

